In some recent Digital Outsider columns, I think we established that "digital" isn't a medium -- but instead, a format that enables programming and advertising content to be rendered in malleable ways that make various media platforms -- especially out-of-home ones -- much more dynamic than they could possibly be via static, analog formats.

In the past outdoor advertisers could breezily dismiss local restrictions on digital out-of-home video advertising by pointing to the First Amendment, whose protection of public speech traditionally made it very difficult to prohibit advertising, as long as it wasn't false or misleading. But in recent months local politicians in Los Angeles have launched a concerted effort to pass municipal codes that will halt and possibly roll back the digital tide in this southern California metropolis.

There was more movement (a bit convoluted) in the digital out-of-home space this week, as the Out-of-home Video Advertising Bureau inducted two new members, Adcentricity and Ecast, with Adcentricity also announcing that it added Ecast to its own roster of digital out-of-home networks. Adcentricity also said it has signed up Provision 3D. The announcements, reminiscent of stacking Russian dolls, are evidence that DO is still kicking even in the face of a sharp economic downturn.